In convention art of a light emitting diode bulb with sensor function, a light emitted diode bulb is disposed with a sensor on its top. The sensor is used for sensing human or ambient light and the light emitting diode bulb is turned on when human enters sensor range of the sensor. Similar technology description may be found in China patent application No. 2005200000991.X and 200810097926.1.
Once a light emitting diode bulb is turned on, the emitted, refracted or reflected light from the light emitting diode bulb may be received by a sensor. This makes the sensor work abnormally and this is the disadvantage of convention art. Accordingly, improvement is needed.